Lutetium trinitrate

Acute Toxicity: oral

Administrative data

Endpoint:

acute toxicity: oral

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From August 23rd, 2016 to February 9th 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

GLP compliance

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 423 (Acute Oral toxicity - Acute Toxic Class Method)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method B.1 tris (Acute Oral Toxicity - Acute Toxic Class Method)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

September 22nd, 2015

Test type:

acute toxic class method

Limit test:

no

Test material

Test material information

Constituent 1

Reference substance name:

Lutetium trinitrate

EC Number:

233-241-7

EC Name:

Lutetium trinitrate

Cas Number:

10099-67-9

Molecular formula:

HNO3.1/3Lu

IUPAC Name:

lutetium trinitrate

Test material form:

solid: crystalline

Details on test material:

- Name of test material: Lutetium trinitrate

Test animals

Species:

rat

Strain:

Wistar

Remarks:

Crl:WI

Sex:

female

Details on test animals or test system and environmental conditions:

TEST ANIMALS
- Source: Charles River Laboratories, Research Models and Services, Germany GmbH, Sandhofer Weg 7, D-97633 Sulzfeld
- Females nulliparous and non-pregnant: yes
- Age at study initiation: 8 - 10 weeks old
- Weight at study initiation: 194 - 227 g
- Fasting period before study: yes
- Housing: Type II polypropylene/polycarbonate
- Diet (e.g. ad libitum): ad libitum, except the night before treatment. Animals received ssniff® SM R/M "Autoclavable complete diet for rats and mice – breeding and maintenance" produced by ssniff Spezialdiäten GmbH, D-59494 Soest Germany (Batch no.: 278 5652, expiry date: November 2016).
- Water (e.g. ad libitum): ad libitum. Tap water from the municipal supply, as for human consumption was available from a 500 mL bottle.
- Acclimation period: yes, at least 8 days

ENVIRONMENTAL CONDITIONS
- Temperature (°C): 20.1 – 25.1°C
- Humidity (%): 32 – 75 %
- Air changes (per hr): 15 – 20 air exchanges/hour
- Photoperiod (hrs dark / hrs light): 12 hours daily, from 6.00 a.m. to 6.00 p.m.

IN-LIFE DATES: From: August 31st, 2016 To: September 23rd, 2016

Administration / exposure

Route of administration:

oral: gavage

Vehicle:

water

Details on oral exposure:

VEHICLE
- Concentration in vehicle: 200 mg/mL
- Amount of vehicle (if gavage): 10 mL/kg
- Justification for choice of vehicle: As the first tested vehicle distilled water was found to be appropriate for the test item, no further testing was required.
- Lot/batch no. (if required): 7170914

MAXIMUM DOSE VOLUME APPLIED: 10 mL/kg

DOSAGE PREPARATION: The test item was freshly formulated at a concentration of 200 mg/mL and 30 mgLu(NO3)3/mL (anhydrous equivalent form; equivalent to 250 mg Lu(NO3)3 ● 6H2O/mL and 37.5 mg Lu(NO3)3 ● 6H2O/mL, respectively, when given in hydrous from, considering concentration factor 1.25) in the vehicle, in the Pharmacy of CiToxLAB Hungary Ltd. on the day of administration. The formulation container was magnetic stirred continuously up to the end of dose administration procedures.

CLASS METHOD (if applicable)
- Rationale for the selection of the starting dose: The initial dose level was selected by the Study Director to be that which is most likely to produce mortality in some of the dosed animals. In the lack of any preliminary toxicological information, 2000 mg/kg bw (anhydrous equivalent form; equivalent to 2500 mg Lu(NO3)3 ● 6H2O/kg bw) was selected to be the starting dose.

Initially, 3 female animals were treated with 2000 mg/kg bw of Lutetium trinitrate (active ingredient). No mortality was observed, therefore further 3 animals were treated at the dose level of 2000 mg/kg bw. Three animals died after 1 day observation, thus the next dosed group was administered at 300 mg/kg bw (anhydrous equivalent form; equivalent to 375 mg Lu(NO3)3 ● 6H2O/kg bw). As no mortality was observed in this group, a confirmatory group was dosed at the same dose level. As mortality was not observed in the confirmatory group, further testing was not required according to the test guidelines (OECD 423, Commission Regulation (EC) NO 440/2008 of 30 May 2008, B.1.Tris).

Doses:

2000 mg/kg bw (anhydrous equivalent form; equivalent to 2500 mg Lu(NO3)3 ● 6H2O/kg bw) and 300 mg/kg bw (anhydrous equivalent form; equivalent to 375 mg Lu(NO3)3 ● 6H2O/kg bw)

No. of animals per sex per dose:

3 per group

Control animals:

no

Details on study design:

- Duration of observation period following administration: 14 days
- Frequency of observations and weighing: Clinical observations were performed on all animals at 30 minutes, 1, 2, 3, 4 and 6 hours after dosing and daily for 14 days thereafter. The body weight was recorded on the day before treatment (Day -1), on the day of the treatment (Day 0) and weekly thereafter or when the day of death.
- Necropsy of survivors performed: yes
- Other examinations performed:
* clinical signs: Individual observations were performed on the skin, fur, eyes, mucous membranes, respiratory, circulatory, autonomic and central nervous system, somatomotor activity and behaviour pattern. Particular attention was directed to observation of tremors, convulsions, salivation, diarrhoea, lethargy, sleep and coma.
* necropsy: Macroscopic examination was performed on all animals. After examination of the external appearance, the cranial, thoracic and the abdominal cavities were opened and the organs and the tissues were observed. Macroscopic abnormalities were recorded.

Statistics:

Not applicable
The method used was not intended to allow the calculation of a precise LD50 value.

Results and discussion

Effect levels

Key result

Sex:

female

Dose descriptor:

LD50

Effect level:

> 300 - <= 2 000 mg/kg bw

Based on:

act. ingr.

Mortality:

Lutetium trinitrate caused the death of 3/6 female rats to Day 1 at a dose level of 2000 mg/kg bw.

Clinical signs:

other: * In the first group at the dose level of 2000 mg/kg, incoordination (up to Day 1), decreased activity (up to Day 1), hunched back (up to Day 3) and piloerection (up to Day 2) were observed in 3/3 animals. From Day 4 all animals were symptom-free. * In t

Gross pathology:

White firm material (within digestive contents) adhered to the glandular stomach mucosa were found in the 3/3 found dead females dosed at 2000 mg/kg bw (confirmatory group) and was considered to be the administered test item. Changes in the lungs were regarded as agonal or post mortem. No changes were observed in other organs.
Dark-red multifocal discolorations of the glandular stomach mucosa observed in 3/3 surviving females dosed at 2000 mg/kg bw and euthanized on Day 14 (first group), were regarded as test item-related. No changes were observed in other organs.
No gross changes were recorded at a dose level of 300 mg/kg bw in both groups, first and confirmatory group.

Other findings:

The dose levels were calculated to anhydrous form considering the purity of the test item. Concentration factor was 1.25. Based on this, the applied anhydrous dose levels were 2000 mg Lu(NO3)3/kg bw (equivalent to 2500 mg Lu(NO3)3 ● 6H2O/kg bw) and 300 mg Lu(NO3)3/kg bw (equivalent to 375 mg Lu(NO3)3 ● 6H2O/kg bw).

Applicant's summary and conclusion

Interpretation of results:

Category 4 based on GHS criteria

Conclusions:

Under the conditions of this study, the acute oral LD50 value of the test item Lutetium trinitrate was found to be between 300 and 2000 mg Lu(NO3)3/kg bw (anhydrous equivalent form), in female Crl:WI rats.

Executive summary:

The single-dose oral toxicity of Lutetium trinitrate (Lu(NO3)3 was performed according to the acute toxic class method (OECD 423 and Commission Regulation (EC) No 440/2008 of 30 May 2008, B.1.Tris) in Crl:WI female rats.

Four groups of 3 female Crl:WI rats were treated with the test item at a dose level of 2000 mg Lu(NO3)3/kg bw (anhydrous equivalent form;equivalent to 2500 mg Lu(NO3)3 ● 6H2O) (Group 1, 2) and 300 mg Lu(NO3)3/kg bw (anhydrous equivalent form; equivalent to 375 mg Lu(NO3)3 ● 6H2O) (Group 3, 4).

A single oral treatment was carried out by gavage for each animal after an overnight food withdrawal. Food was made available again 3 hours after the treatment. The test item was formulated in distilled water at a concentration of 200 and 30 mg Lu(NO3)3/mL anhydrous equivalent form at a dose volume of 10 mL/kg bw. Correction factor of 1.25 was applied considering the Lu(NO3)3 content. Concentration was calculated to anhydrous form.

Initially, three females (Group 1) were treated at a dose level of 2000 mg/kg bw. As no mortality but several symptoms were observed, a confirmatory group (Group 2) was treated after six days at the same dose level. Since all animals died in Group 2, further two groups (Group 3, 4) were administered at dose level 300 mg/kg bw. As no mortality was observed at 300 mg/kg bw, therefore no further testing was required according to OECD 423 and Commission Regulation (EC) NO 440/2008 of 30 May 2008, B.1.Tris.

Clinical observations were performed at 30 minutes, 1, 2, 3, 4 and 6 hours after dosing and daily for 14 days (or until death) thereafter. Body weight was measured on Days -1, 0 and 7 and before necropsy. All animals were subjected to a necropsy and a macroscopic examination.

The results of the study were summarized as follows:

Mortality: Lutetium trinitrate caused the death of 3/6 female rats to Day 1 at a dose level of 2000 mg/kg bw.

No mortality was observed at dose level of 300 mg/kg bw.

Clinical Observations: In the first group at the dose level of 2000 mg/kg bw, incoordination (up to Day 1), decreased activity (up to Day 1), hunched back (up to Day 3) and piloerection (up to Day 2) were observed in 3/3 animals. From Day 4 all animals were symptom free.

In the confirmatory group at dose level of 2000 mg/kg bw, incoordination, decreased activity, hunched back, piloerection and prone position were observed in 3/3 animals. Additional symptom of cold to touch was noted in 1/3 animal on the day of death (Day 1).

At the dose level of 300 mg/kg bw, only hunched back was noted on the day of treatment in 1/6 animal. To Day 1 this animal became symptom-free. 5/6 animals were symptom-free during the whole observation period.

Body Weight and Body Weight Gain: There was a slight bodyweight lost (-2 g) in one animal in the confirmatory group of 300 mg/kg bw between Day 7 and 14. Since the bodyweight loss was not a tendency in the group this observation could be incidental.

There were no effects on body weights or body weight gains that could be attributed to treatment in the surviving animals at 2000 mg/kg bw.

Necropsy: White firm material (within digestive contents) adhered to the glandular stomach mucosa were found in the 3/3 found dead females and was considered to be the administered test item. Other changes were regarded as agonal or post mortem.

Dark-red multifocal discolorations of the glandular stomach mucosa observed in 3/3 surviving females received 2000 mg/kg bw and euthanized on Day 14, were regarded as test item-related.

No gross changes were recorded at a dose level of 300 mg/kg bw.

Conclusion: Under the conditions of this study, the acute oral LD50 value of the test item Lutetium trinitrate was found to be between 300 and 2000 mg Lu(NO3)3/kg bw (anhydrous equivalent form), in female Crl:WI rats.

According to the GHS criteria, Lutetium trinitrate can be ranked as "Category 4" for acute oral exposure.